Bipolar electrochemistry is a field dealing with phenomena where an electric conductor functions as a bipolar electrode when being immersed in a solution to which a voltage is applied. Various applications of the bipolar electrode have been reported since around 2000 such as electrochemical devices and electrode chips (see S. E. Fosdick, K. N. Knust, K. Scida, R. M. Cooks, Angew. Chem. Int. Ed. 52, 10438 (2013) (NPL 1)).
We have been developing a closed bipolarelectrode system (also referred to as “cBPES”) in which a driving electrode and a potentiostat are used instead of a salt bridge and a liquid junction that electrically connect a measurement cell and an auxiliary cell in a regular conversion stripping method (see Chemical Sensors, Vol. 31 Supplement B (2015) (NPL 2), and Shinichiro Takano, Kumi Y. Inoue, Miho Ikegawa, Yasufumi Takahashi, Kosuke Ino, Hitoshi Shiku, Tomokazu Matsue (2016) Electrochemistry Communications in press (NPL 3)). This system can solve the problems of the conventional method such as salt precipitation and clogging in the salt bridge and liquid junction.